Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 12 of 12 for “"Oxygen Dynamics"”.
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Characterizing water quality, nutrients, and dissolved oxygen dynamics in four Lake Ontario coastal wetlands
… aimed to improve our understanding of phosphorus dynamics in these wetlands. Continuous multiparameter sondes (dissolved oxygen, conductivity, turbidity, pH) were deployed above sediments, collecting data every 30 minutes, accompanied by weekly water samples. Key findings include a shift in algal …
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Oxygen dynamics in the bottom waters of lakes: Understanding the past to predict the future
Dissolved oxygen concentrations are declining in the bottom waters of many lakes around the world, posing critical water quality concerns. Throughout my dissertation, I assessed how bottom-water dissolved oxygen may mediate the effects of climate and land use change on water quality in lakes. …
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A novel non-invasive optical method for quantitative visualization of pH and oxygen dynamics in soils
… to access the spatial distribution and temporal dynamics of these parameter. Noninvasive imaging techniques with high spatial and temporal resolution overcome these limitations. And new non-invasive techniques are needed to study the dynamic interaction of plant roots with the surrounding soil, …
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A Statistical Model for the Prediction of Dissolved Oxygen Dynamics and the Potential for Hypoxia in the Mississippi Sound and Bight
<p>Hypoxia events occur when dissolved oxygen concentrations fall below the minimum threshold (dissolved oxygen concentrations < 2 mg O<sub>2</sub> L<sup>-1</sup>) necessary to avoid respiratory distress among aquatic organisms. In the Mississippi Sound and Bight, hypoxia is most prevalent from …
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Impacts of the non-native aquatic plant water chestnut, Trapa natans, on inland freshwater nitrogen and oxygen dynamics, and host-specificity testing of the biological control insect, Galerucella birmanica
… of this thesis, I present seasonal dissolved oxygen and nitrate concentrations of water samples collected from within and outside of three T. natans beds in New York State, US. These environmental characteristics are known to be impacted in other habitats invaded by T. natans and can prompt …
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Assessment of oxygen sources and sinks in the northern Gulf of Mexico using stable oxygen isotopes
… biological and physical processes that control oxygen dynamics. Yet, based on oxygen concentration measurements alone, it is difficult to separate the effects of biological factors from physical factors. To address this problem, I used a dual budget approach to assess the importance of oxygen …
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Understanding key factors influencing habitat quality for the endangered fountain darter (Etheostoma fonticola) in the Comal River.
… and a spatial study of diel dissolved oxygen dynamics. Nutrient data were collected via water samples, nutrient diffusing substrata (NDS), sediment cores, and plant samples. The water samples and NDS results indicated a severe phosphorus limitation in the water column and some …
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Probing Control of Glucose Feeding in Escherichia coli Cultivations
… formation can be made using a standard dissolved oxygen sensor. This information is used in a feedback algorithm that adjusts the feed rate to avoid acetate formation while maintaining a high glucose supply. The feed rate is also restricted to ensure aerobic conditions when the maximum oxygen …
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Extremum-Seeking Control of Industrial-Scale Fermentation Processes
… of the frequency spectrum of the dissolved oxygen measurement following a periodic perturbation in the feed rate. A controller based on this strategy was tested in pilot scale, where it gave higher specific growth rates and lower concentrations of overflow metabolites during the exponential …
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HYPORHEIC FLOW, RESIDENCE TIMES AND NITROGEN REACTIONS IN A RIFFLE-POOL SEQUENCE, TRUCKEE RIVER, NV.
… investigates hyporheic flow, residence times, oxygen dynamics and nitrogen transformations of a riffle-pool sequence in the lower Truckee River. The overall objectives of this research are to examine the physical and chemical controlling variables of nitrogen cycling in the hyporheic zone. The …
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Seizures Cause Long-Lasting Analgesia and Short-Lasting Hyperoxia
… of postictal analgesia. I also examined brain oxygenation in the locus coeruleus – a region involved in the descending modulation of pain – before, during, and after maximal electroconvulsive stimulation-induced seizures. Methods: The nociceptive perception of mice before and after a seizure …